Today's market for mobile electronics has driven connector manufacturers to push the limits of miniaturization to produce smaller and smaller connectors for FPC and FFC. These miniaturized connectors use thinner plastics and smaller contacts and achieve lower contact forces. As a result, a segment of the market has been left out which is those manufacturers whose product's primary requirement is ruggedness and reliability. These products are generally in the military, aviation, medical, and automotive markets.
ZIF style interconnects have several benefits. First, when an FPC or FFC is inserted into or removed from the connector, there is no wiping of the contact and conductor surface which results in less surface plating wear compared to non-ZIF style connectors. This makes the connectors particularly suited to gold-plated contacts which do not require contact wiping to remove surface oxidation from the contact surfaces. Using gold-plated contacts requires less contact force for a reliable connection so contacts and connectors may be reduced in size compared to contacts with tin or nickel plating. Also, since there is no contact wipe, and therefore very little wear on the contact surface, the contacts are suitable for multiple insertion and extraction cycles.
Due to their reduced size, modern ZIF connectors use minimal contact force to make an electrical connection. They also have a very small allowable deflection range, which is typically only a few thousandths of an inch, to achieve the industry accepted standard contact force for gold-plated electrical contacts of 30 grams nominal with 10 grams minimum. With such a small deflection range, and when the FPC or FFC are at the minimum thickness tolerance, the connection may not provide the minimum contact force. As a result, these connectors are more prone do discontinuity in environments where the connector will be subject to shock and vibration conditions which may induce motion and cause the contact to deflect.
ZIF connectors use a Normally Open (NO) contact configuration which uses either a rotating or sliding actuator to reduce the contact gap which applies pressure to engage the contact with the FPC or FFC to make the electrical contact. The contact only provides the proper contact force when this actuator is fully engaged. Any movement or disengagement of the actuator induced by shock or vibration may disengage the contact from the FPC or FFC and cause an electrical discontinuity. This feature is what makes ZIF connectors inherently poorly suited to conditions with high shock and vibration. Also, in some designs, any significant movement of the FFC or FPC can dislodge the actuator which releases the contact pressure and causes an electrical discontinuity. This is commonly addressed by having to incorporate additional hardware to fix the FFC or FPC in position outside the connector to provide strain relief.